An American study of a huge number of children several years ago found that 70% of MEIs were caused by food allergies – chiefly dairy, components of wheat (NOT GLUTEN!), egg white and yeasts. These allergens promote the secretion of mucus in the middle ear and the Eustacian tube (which runs between back of upper throat and middle ear). Bacteria flourish in the stagnant mucus and lead to infection. Getting rid of the infection and identification of food allergies, then avoidance, is the apt course of action. This would save an enormous amount of invasive surgery (and cost to the government) and the insertion of grommets.